Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Infection And Immunity > Sepsis and Innate Immunity > Flashcards

Sepsis and Innate Immunity Flashcards

(51 cards)

Start Studying
1
Q

Define sepsis

A

Life threatening organ dysfunction due to a dysregulated host response to infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define septic shock

A

Persisting hypotension requiring treatment to maintain blood pressure despite fluid resuscitation already being given

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define bacteriaemia

A

The presence of bacteria in the blood
Not multiplying
No symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does the early warning score for sepsis look for?

A

Increased resp rate
Increased heart rate
Very low or high temperature
Low blood pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is included in the sepsis six bundle?

A 
Give high flow oxygen
Give IV fluids 
Give empirical IV antibiotics 
Take blood for cultures
Take blood for lactate 
Check the urine output
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Apart from the sepsis six bundle, what other investigations should you order?

A 
FBC
U&E
EDTA bottle for PCR 
Blood sugar
LFTs
CRP 
Coagulation studies
Blood gases
Other microbiology samples (CSF, urine)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the most likely organism causing meningitis?

A

Neisseria meningitidis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is meningitis spread?

A

Direct contact with respiratory secretions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the local effects of cytokines?

A

Promote wound repair

Recruit the reticuloendothelial system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the systemic effects of cytokines?

A

Stimulating growth factor, macrophages and platelets to control infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can cytokines in sepsis lead to organ ischaemia?

A

Initiate production of thrombin
Promote coagulation
Cytokines also inhibit fibrinolysis
Microvascular thrombosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the management for sepsis

A

Sepsis six bundle
Consider early referral to ITU
Regular monitoring and reassessment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What antibiotic do we use to treat meningitis?

A

Ceftriaxone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe neisseria meningitidis

A 
Gram negative diplococcus 
Numerous types - B is most common in UK
Type based on capsular antigen 
Up to 25% young adults are carriers
Spread by aerosols and nasal secretions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What types of meningitis are covered in the multiple vaccine?

A

ACWY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define infectivity

A

Capacity of microorganism to establish itself within the host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define virulence

A

Capacity of the pathogen to harm the host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the immune system?

A

All the cell and organs that contribute to the immune defences against infectious and non-infectious conditions
Distinguishing between self and non-self

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define an infectious disease

A

When the pathogen succeeds in evading and/or overwhelming the host’s immune defences

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the roles of the immune system?

A

Pathogen recognition
Containing/eliminating the infection
Regulating itself
Remembering pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Name the 4 types of barriers that are the first line of defence

Study These Flashcards
A

Physical
Physiological
Chemical
Biological

22
Q

Describe the physical barriers of defence

Study These Flashcards
A

Skin (epidermis has no vessels so cannot spread that way)

Mucous membranes - active and dynamics, secrete antimicrobials, cilia

23
Q

Describe some physiological barriers against infection

Study These Flashcards
A

Diarrhoea
Vomiting
Coughing
Sneezing

24
Q

Describe the chemical barriers against infection

Study These Flashcards
A

Low pH of the skin, stomach and vagina - Bacteria are extremely sensitive to acidic environments
Antimicrobial molecules: IgA (tears, salvia), Lysozyme (perspiration, urine, sebum), mucus, beta-defensins (epithelium), gastric acid

25
Describe the benefits of normal flora
Compete with pathogens for attachment sites and resources Produce antimicrobials Synthesis vitamins (K, B12 and other B vitamins)
26
Give some examples of normal flora of the skin
``` Staph aureus Staph epidermidis Strep pyogenes Candida albicans Clostridium perfringens ```
27
Give some examples of normal nasopharyngeal flora
Strep pneumoniae Neisseria meningitidis Haemophilus species
28
List some patients who are high risk when present with bacteriaemia
Asplenic/hyposplenic Damaged/prosthetic valves Previous infective endocarditis
29
What pathologies can lead to overgrowth of normal flora?
Diabetes AIDS Malignancy Chemotherapy
30
What are the 3 main phagocytes?
Macrophages Monocytes Neutrophils
31
Describe the features of macrophages
Present in all organs Ingest and destroy microbes Present antigens to T cells Produce cytokines/chemokines
32
Describe the features of monocytes
Present in blood | Recruited at infection site and differentiate into macrophages
33
Describe the features of neutrophils
Present in the blood Increased during infections Recruited by cytokines to site of infection Ingest and destroy microbes
34
What are PAMPs?
Pathogen-associated molecular patterns Present on the microbe What the phagocytes use to recognise it Can be carbohydrate, lipid, protein or nucleic acid
35
Define opsonisation
Coating proteins called opsonins that bind to microbial surfaces leading to enhanced attachment of phagocytes and clearance of microbes
36
Give some examples of opsonins
Component - C3b, C4b Antibodies - IgM, IgG Acute phase proteins - CRP, MBL
37
Encapsulated bacteria cannot be cleared unless ...
Opsonised
38
Give examples of some encapsulated bacteria
Neisseria menigitidis Strep pneumoniae Haemophilus influenzae B
39
What are the steps of phagocytosis?
``` Chemotaxis and adherence to microbe Ingestion Formation of phagosome Fusion with lysosome Digested on microbe by enzymes Formation of residual body containing indigestible material Discharge of waste material ```
40
What are the 2 types of phagocyte killing mechanisms?
``` Oxygen dependent (respiratory burst) Oxygen independent ```
41
What factors contribute to the oxygen independent killing mechanism?
Lysozyme Lactoferrin/transferrin Cationic proteins Proteolytic and hydrolytic enzymes
42
How may complement proteins are there?
20
43
Describe the 2 complement activating pathways
Alternative - initiated by cell surface microbial constituents MBL - initiated when MBL binds to mannose containing residues of proteins found on many microbes
44
Which complement proteins recruit phagocytes?
C3a and C5a
45
Which complement proteins contribute to the membrane attack complex?
C5-C9
46
What are the actions of TNF-alpha, IL-1 and IL-6?
``` CRP and MBL released Neutrophil mobilisation Vasodilation Vascular permeability Adhesion molecules attract neutrophils Increase body temperature ```
47
Why are asplenic people susceptible to encapsulated bacteria?
They have reduced phagocytosis | The spleen normally contains many macrophages
48
How can e-coli be caught?
``` Eating contaminated food Touching infected animals Contact with people who have the illness Drinking inadequately treated water Swimming/playing in contaminated water ```
49
Main symptoms of E-coli infection:
Diarrhoea Fever Stomach cramps (Can last up to 2 weeks)
50
Describe a few basic features of E-coli
Gram negative Rod-shaped Anaerobic
51
Describe a few basic features of strep pneumoniae
``` Gram positive Anaerobic Present in many healthy carriers Main cause of CAQ pneumonia Transmission: sneezing, coughing, direct contact Encapsulated ```

Infection And Immunity (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions